Improvement in head-blocks for saw-mills



a. W'ILLETT.

improvement ih Head-Blocks for Saw-MiHs.

No. 130,886, Patented Aug.27,1872.

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UNITED STATES PATENT QFFICE.

-GEORGE WILLETT, OF FRIENDSHIP, NEW YORK, ASSIGNOR TO HIMSELF AND J. W. HILTON, OF BRADFORD, PENNSYLVANIA.

IMPROVEMENT IN HEAD-BLOCKS FOR SAW-MILLS.

Specification forming part of Letters Patent No. 130,886, dated August 27, 1872.

' invented by GEORGE WILLETT, of Friendship,

in the county of Allegany and State of New York.

- Figure l isa top view of my improved headblock for saw-mills. Fig. 2 is a bottom view of the same; Fig. 3, a vertical longitudinal section; and Fig. 4, a vertical transverse section of the same.

Similar letters of reference indicate corresponding parts.

This invention relates to a new mechanism for feeding the head-blocks of saw-mills in the carriages; and consists in the employment of two reciprocating ratchet-bars, which are operated by crank connection with a rock-shaft, and with which sprin g-pawls, that are attached to the head-block, are in contact, so fashioned that when the ratchets are moved alternately back and forth the one moving forward will actuate the head-block in the desired manner, the other ratchet meanwhile moving back to be ready for its next forward movement, during which to actuate the carriage.

A in the drawing represents the cross-piece of the saw-carriage, by which the head-block B is supported. This cross-piece is slotted and grooved at the sides of the slot, to receive and hold down the lower part of the head-block, as is clearly indicated in Fig. 4. Below the head-block are arranged, at the inner sides of the slotted cross-piece A, two ratchet-bars, a b, which extend nearly from end to end of the cross-piece. Both of these bars are, by rods d d, connected with cranks of a rock-shaft, 0, that hangs in the back part of the cross-piece A. When the shaft 0 is vibrated, by suitable means, one of the bars, a or b, is moved forward and the other back, and vice versa, alternately. Spring-pawls e f, attached to the lower part of the head-block, are in contact, respectively, with the toothed edges of the ratchet-bars a b. When, by the oscillation of the rock-shaft, one of the.bars a b is moved forward and the other back, the one moving forward will push the pawl in contact with it forward, thereby feeding the head-block in the desired manner, the other receding bar meanwhile slipping on its pawl, ready to push the same during its subsequent forward motion. The pawls are held or spread against the bars a b by their own spring-power. When the head-block is to be moved back the pawls must be drawn toward each other and away from the bars a b. This is done by means of two pins, g h, which proj eet downward from a plate, 1', that is formed at the lower end of an arbor, j, whose bearings are in the head-block. A handle, Z, applied to the upper end of the arborj is used for turning'the same and bringing the pins g h against the pawls, thereby swinging the latter out of gear.

Having thus described my invention, I claim as new and desire to secure by Letters Patcut-- The two ratchet-bars a b, rods d d, and rockshaft 0, combined with a head-block, B, having spring-pawls cf, arranged as and for the purpose described.

GEORGE WILLETT. Witnesses:

A. I. BLooD, PERRY WHALEY. 

